Multi-mode image sensor

An apparatus comprising:

• an array of pixel cells, each pixel cell of the array of pixel cells including one or more photodiodes configured to generate charge in response to light, and a charge storage device to convert the charge to output a voltage;
• first analog-to-digital converters (ADCs), each first ADC being associated with a pixel cell or a block of pixel cells of the array of pixel cells;
• second ADCs, each second ADC being associated with a column of pixel cells or a column of blocks of pixel cells of the array of pixel cells;
• and
• a controller configured to:
• in a first mode, enable at least a subset of the first ADCs to perform a quantization operation of the voltages output by at least a subset of the pixel cells or the blocks of pixel cells associated with the at least the subset of the first ADCs in parallel to generate a first image frame;
• and
• in a second mode, enable at least a subset of the second ADCs to perform quantization operations sequentially of the voltages output by pixel cells or blocks of pixel cells within at least a subset of the columns of pixel cells or the columns of blocks of pixel cells associated with the at least the subset of the second ADCs to generate a second image frame.